Too cold to start car

It's about 50 degrees today and I started the car right up. Took a few tries to keep it running but it turned over quite easily with just a few pumps, as it normally does when it's cold. I get that I still need a choke, but honestly I've driven the car for 4 years without one.

However, it idles rough and I can hear what sounds like a lot of subtle misfires when I get on the gas. So something definitely isn't right.